Today I've been checking out iTunes U for the first time. It's been around a few years so I'm not sure why I hadn't looked at it before. But if you haven't checked it out either it is a specialized area of the Apple iTunes store that enables Higher Ed institutions to make audio/visual content available for download and subscription.
According to Wikipedia the service was 'created to manage, distribute, and control access to educational audio and video content and PDF files for students within a college or university as well as the broader Internet.' Wikipedia says that 'an advantage iTunes U has over traditional podcasting tools is that access to content can be restricted because of the use of the iTunes infrastructure end-to-end' and apparently there are now over 75,000 files available to download.
If you have the technical / professional infrastructure to support and market your own eLearning system and you're looking for a content distribution tool for your institution, rather than a full-blown Learning Management System, it's worth checking out. With iTunes U you can create a 'single home for all the digital content created or curated by educators, which can then be easily downloaded and viewed on any Mac, PC, iPod, or iPhone' (from the website).
While mobile learning (mLearning) adoption rates continue to increase I can only see this becoming much more popular, especially for some of the smaller institutions. Already the big guys like Stanford, Yale, MIT, Oxford, and UC Berkeley distribute their content publicly using the iTunes store, so it is already a 'success'.
Here's some more information from their website: Let the learning begin